1. Field of the Invention
This invention relates to physical exercise apparatus for use in developing human muscles.
2. Prior Art
The human body has a substantial number of muscle groups and in the past various types of mechanical exercise equipment have been used to increase both muscular strength and size. However, prior exercise devices have either been relatively complex or limited in versatility and efficiency in terms of the number of muscle groups an individual apparatus could adequately develop.
Physiological studies have shown that in most cases power output or strength exerted by the human limbs or trunk actually varies in intensity throughout the normal range of motion of these body parts, due to the unique interaction of muscular strength curves and skeletal leverage, and that maximal contraction of muscle fiber occurs when a muscle is sustained in a static or isometric contractile state.
Therefore, throughout the range of an exercise movement, resistance should, in most cases, match the power output of the contracting muscle or muscles, and ideally a static or isometric contraction should be experienced within the terminal range of the movement.
Designers of prior exercise equipment have failed to recognize this principle and have provided resistance curves, inadequate in terms of generating maximum contraction of muscle fiber at the position of greatest musculoskeletal strength advantage.